小编典典

使用JavaScript从数组中删除对象

javascript

如何从数组中删除对象?我想删除,其中包括名称的对象KristiansomeArray。例如:

someArray = [{name:"Kristian", lines:"2,5,10"},
             {name:"John", lines:"1,19,26,96"}];

我要实现:

someArray = [{name:"John", lines:"1,19,26,96"}];

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2020-04-25

共1个答案

小编典典

您可以使用多种方法从数组中删除项目:

//1
someArray.shift(); // first element removed
//2
someArray = someArray.slice(1); // first element removed
//3
someArray.splice(0, 1); // first element removed
//4
someArray.pop(); // last element removed
//5
someArray = someArray.slice(0, a.length - 1); // last element removed
//6
someArray.length = someArray.length - 1; // last element removed

如果要删除position处的元素x,请使用:

someArray.splice(x, 1);

要么

someArray = someArray.slice(0, x).concat(someArray.slice(-x));

您可以使用Array.filterArray.splice结合使用Array.findIndex参见MDN从数组中删除一个或多个元素,例如

// non destructive filter > noJohn = John removed, but someArray will not change

let someArray = getArray();

let noJohn = someArray.filter( el => el.name !== "John" );

log("non destructive filter > noJohn = ", format(noJohn));

log(`**someArray.length ${someArray.length}`);



// destructive filter/reassign John removed > someArray2 =

let someArray2 = getArray();

someArray2 = someArray2.filter( el => el.name !== "John" );

log("", "destructive filter/reassign John removed > someArray2 =",

  format(someArray2));

log(`**someArray2.length ${someArray2.length}`);



// destructive splice /w findIndex Brian remains > someArray3 =

let someArray3 = getArray();

someArray3.splice(someArray3.findIndex(v => v.name === "Kristian"), 1);

someArray3.splice(someArray3.findIndex(v => v.name === "John"), 1);

log("", "destructive splice /w findIndex Brian remains > someArray3 =",

  format(someArray3));

log(`**someArray3.length ${someArray3.length}`);



// Note: if you're not sure about the contents of your array,

// you should check the results of findIndex first

let someArray4 = getArray();

const indx = someArray4.findIndex(v => v.name === "Michael");

someArray4.splice(indx, indx >= 0 ? 1 : 0);

log("", "check findIndex result first > someArray4 (nothing is removed) > ",

  format(someArray4));

log(`**someArray4.length (should still be 3) ${someArray4.length}`);



function format(obj) {

  return JSON.stringify(obj, null, " ");

}



function log(...txt) {

  document.querySelector("pre").textContent += `${txt.join("\n")}\n`

}



function getArray() {

  return [ {name: "Kristian", lines: "2,5,10"},

           {name: "John", lines: "1,19,26,96"},

           {name: "Brian", lines: "3,9,62,36"} ];

}


<pre>

**Results**



</pre>
2020-04-25